Mutation induction by the direct treatment of Bacillus subtilis deoxyribonucleic acid.

A procedure was developed to select for specific mutations obtained by means of transformation with DNA previously exposed to potentially dangerous chemical compounds. The 70% co-transformation of hisB and trpC genes in Bacillus subtilis provided a convenient opportunity to select for new mutations. When purified DNA from wild type bacteria was treated with N(OH) acetyl aminofluorene or Hoechst dye 37 507 and used to transform a recipient bearing of a trpC2 mutaion, a high proportion of the Trp+ transformants had new hisB mutations.